LL Grammars without e-rules
Definition: Let G = (N, T, P, S) be a CFG without e-rules. G is an LL grammar if for every a Î T and every A Î N there is no more than one rule
A ® X1X2...Xn Î P such that a Î First(X1X2...Xn)
Illustration:
A
X1
X2
Xn
…
Rule r1:
A
Y1
Y2
Ym
…
Rule r2:
a
 x1
a
 x2
Table:
...
a
...
...
...
A
a(A, a)
a
a Î First(X1X2...Xn)
a Î First(Y1Y2...Ym)
Ruled out in an LL grammar
Only rule r1:     A ® X1X2…Xn
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